<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div id="app">
    <h2>{{message}}</h2>
    <h2>{{getFullName}}</h2>
    <h2>{{fullName}}</h2>
</div>

<script src="../js/vue.js"></script>
<script>
    const app = new Vue({
        el: "#app",
        data: {
            firstName: 'kebi',
            lastName: 'yujinbiao'
        },
        methods: {
            getFullName: function () {
                return this.firstName + '' + this.lastName;
            }
        },
        computed: {
            fullName: function () {
                return this.firstName + '' + this.lastName;
            }
        }
    })
</script>
</body>
</html>